Locomotive firebox equipment



July 14, 1942.

c. A. SIEGEL LOCOMOTIVE FIREBOX EQUIPMENT Original. Filed Aug. 12, 1937 '2' sheets-sheet 1 July 14, 1942. c. A. SIEGEL LOCOMOTIVE FIREBOX EQUIPMENT 2 Shee1isSheet 2 Original Filed Aug. 12, 19s? 9 T b 7 H 9 J 2 Z 5 5 LFJ 2 w v 2 w x zn lr/k \M v z 4, i H U W TOR $4 ATTORNEYS Patented July 14, 1942 K T LOCOMOTIVE FIREBOX EQUIPMENT Chester A. Siegel, Newark, N. J., assignor to American Arch Company, New York, N. Y., a corporation of Delaware Original application August 12, 1937, Serial No.

158,688. Divided and this application June 21, 1941, Serial No. 399,134

3 Claims, (o1. 122--68) This invention relates to locomotive firebox equipment and is of especial advantage in connection with a locomotive boiler having toward its rear end a combustion chamber adjoining the firebox, although it is to be understood that not allfeatures of the invention are limited in their 1application and usefulness to a locomotive of this The invention is concerned with a number of in the past resulted in serious explosions, with consequent injury and extensive damage.

How the foregoing objects and advantages are attained, together with others which will occur to those skilled in the art will be more apparent from the following description referring to the accompanying drawings, in which- Figure 1 is a vertical longitudinal sectional view through the rear end portion of a locomoimprovements relating, first, to bracing or tive boiler and firebox, with the improvements strengthening the structure of the firebox and of this invention applied the e of the adjoining combustion chamber, second, Figure 2 is a transverse sectional view taken simplification of the refractory fire arch employed through the firebox substantially on the line 2-2 in the firebox, and third, improvement in the cirof Figure 1; culation in the water walls surrounding the fire- 5 Figure 3 is a transverse sectional View taken box and combustion chamber. through the combustion chamber substantially With regard to the first of the three points on the line 3-3 of Figure 1; and mentioned above it should be borne in mind that Figure 4 is a view similar to Figure 1 illustratbecause of the pressure carried in the boiler and ing a; modified form of construction. thus in the water walls, the inner sheets de- Referring first to the embodiment of Figures 1 fining the combustion chamber and the firebox to 3 inclusive, the outer boiler shell is indicated must be effectively and rigidly stayed or braced. at 5, this shell being joined at its rear edge with For this purpose the side sheets of the firebox are outer sheets surrounding the firebox including commonly provided with a multiplicity of staythe outer top sheet 6 and the outer throat sheet bolts, the crown sheet with crown stays, and 20 l. The top or wrapper sheet 6 is curved downthe combustion chamber with combustion wardly at the sides and has substantially flat porchamber stays. According to this invention adtions 8-8 at opposite sides of the firebox joined ditional bracing is provided for the inner sheets with the mud ring 9 which surrounds the lower defining both the firebox proper and the combusedge of the firebox. The sheet l0 completes tion chamber, by means of circulator devices the closure at the rear end. which are configured and located in a novel man- The firebox proper is defined by side sheets ner to accomplish this purpose. Other factors H.Il attached at their lower edges to the mud in this connection will be pointed out more fully ring and usually formed integrally with the hereinafter following a description of the accomcrown sheet [2. An inner back sheet [3 cooppanying drawings. 'erates with the sheet ID to form a water leg at As noted above, the invention also has in View the rear of the firebox through which a fire door improvement in the refractory arch, this im- I4 is provided. The crown sheet I2 extends forprovement consisting in arrangement of the cirwardly over the combustion chamber l5 which culator elements employed to afford better and extends into the boiler shell 5, and in this region more convenient support for the brick of which the crown sheet is curved downwardly in spaced the arch is composed and also to provide for the relation to the lower portion of the boiler shell use of only a few brick patterns throughout the as seen at It in Figure 3 to define the sides and entire arch. bottom of the combustion chamber. An inner Still further, improved circulation is provided throat sheet I! joined to the mud ring and the especially in the water walls surrounding the rearward edge of the lower part It completes the combustion chamber and the circulator devices jacket at the throat ofth'e firebox. employed provide for delivery of water to the Flue sheet [8 defines the front end of the comcrown sheet in a plurality of zones not only bustion chamber and receives the rear ends of over the firebox but also over the combustion the fiue tubes I9 which extend forwardly in the chamber. boiler.

Various of the foregoing features are of importance in reducing staybolt failure particularly at the top of the firebox and combustion chamber, this being of very substantial importance for the reason that staybolt failures have The foregoing general structure is of known design, and in addition it has been common to stay the inner and outer plates or sheets defining the water walls as by means of bolts someof which are shown diagrammatically at 20. For

the sake of clarity only a few of such stays or bolts have been indicated in the drawings.

As in my prior Patents Nos. 1,894,613 and 2,023,620, I prefer to employ a series of water circulating devices in the firebox, each device interconnecting the side sheets with the crown sheet. In the present application, however, the devices for this purpose are of improved form and con figuration. Each one includes an upper outlet portion 2| at least the upper part of which is preferably of substantially circular cross-section extending perpendicular to the crown sheet. The lower part of each element 2| in accordance with this invention is curved somewhat .rearwardly as at 22 (see Figure 1) to extend at its lower end substantially perpendicularly with respect to the mean plane of the arch. At its lower end the element 2| is joined with the inlet portion for the device consisting of a pair of branches 23 extended somewhat downwardly and laterally toward the side sheets and then approximately horizontally immediately adjacent the side sheets, as clearly seen at 24 in Figure 2. Each of these circulator devices thus in effect incorporates a generally upright outlet portion and a forked inlet portion, the branches 23 of the fork, as with the outlet portion 2|, preferably being of substantially circular cross-section.

Beginning at the rear of the firebox, the several outlet portions for the series, of circulator devices progressively increase in length as is clearly shown in Figure 1, and as further appears in this view, the branches 23 are somewhat arched transversely of the firebox in a plane approximately perpendicular to the mean plane of the arch. The arch brick 25 intervene between the adjacent and parallel inlet branches 2.3 and are supported thereon to form a practically unbroken fire wall at a level adjacent the upper surface of the branches 23. Additional brick .250. bridge the gap between the forward firebox circulator and the throat of the firebox.

By employing circulator devices of the character described, and particularly with the inlet branches 23-23 transversely arched in a plane perpendicular to. the mean planeof the brick arch, a more effective support for the brick is afforded and, in addition, the size and the shape of the brick may be the .same substantially throughout the entire arch. The throat brick 25 are the only ones in this embodiment which are of a diiferent pattern.

Furthermore, by employing outlet connections for the circulatorsv of the type shown at 2| I am enabled more readily than in prior constructions to accommodate the circulator devices to any particular installation, this for the reason that with an outlet connection having a bend intermediate its ends, the outlet. apertures in the, crown sheet maybe shifted somewhat to different positions longitudinally of the firebox. Various boiler appurtenances are commonly associated with the outside wrapper sheet 6 and in making the circulator installation it is necessary to arrange the outlets through the crown sheet in positions to avoid interference with. such appurtenances.

In addition to the foregoing, the present invention also employs a circulator device located at least in large part in the combustion chamber which is frequently provided in the rear end of the boiler shell. This circulator preferably includes inlet branches 26. communicating with the water jacket at the sides of the combustionchamher, and an outlet portion which is upwardly forked to provide branches 2,'|28 lying ina longitudinal vertical plane and connected with the crown sheet in the region thereof above the combustion chamber I5.

This circulator in the combustion chamber is of special advantage for several reasons, including the fact that it provides for constant flow of water over the crown sheet above the combustion chamber which is ordinarily the highest portion of the crown sheet and therefore the first to be exposed in the event of a drop in the water level.

While periodic inspection of the boiler equipment, and proper attention to the gauges will usually avoid an abnormal drop in the water level, from time to time, either through negligence or other causes, the crown sheet, particularly above the combustion chamber is exposed. When this. occurs in an elongated area along the center of the crown sheet, the crown sheet suddenly gives way, resulting in a violent explosion. With regard to this point, it must be borne in mind that the increase in temperature resulting from exposure of the crown sheet weakens the crown stays, so that they will pull out quite readily. By employing the improved circulator in the combustion chamber damage resulting from low water level is largely eliminated since, in addition to providing a constant flow of water over the areas adjacent to the outlets, the circulator constitutes an effective brace or support for the crown sheet. This is especially true when employing a bifurcated outlet, the support being thereby distributed lengthwise along the area which is first exposed upon drop in water level.

I prefer to form all branches of this circulator in the combustion chamber of circular crosssection, since this form of construction affords the strongest bracing.

The. arrangement of Figure 4 is in many respects similar to that of Figures 1 to 3, although in Figure 4 the improvements of this invention have been applied to a locomotive in which the combustion chamber 29 is somewhat shorter than in Figure 1. In Figure 4 all of the circulators employed are arranged in a single arch brick supporting series, but the front circulator device, instead of having a single outlet portion 2|, is here provided with a bifurcated outlet portion having branches 3!! and 3| lying in a vertical longitudinal plane. The forward branch 3| is connected with the crown sheet above the combustion chamber 29 and the rear branch 39 with the crown sheet adjacent the rear edge of the combustion chamber.

In this arrangement, therefore, the front circulator has its inlet branches 23 communicating with the side water legs of the firebox and its outlet branches 33 and 3| communicating with the. space above the crown sheet, and as a result highly effective circulation is provided from the lower forward portions of the side water legs upwardly to the highest point of the crown sheet, i. e., the region in which it is most important to provide against exposure of the crown sheet as well as to provide additional support therefor.

Because of the longitudinally spaced points of support for, and delivery of water to, the crown sheet, provided in accordance with both forms of the invention, in the event of the water level dropping sufiiciently to cause substantial overheating, the crown sheet gives way only in relatively small localized zones so that the boiler pressure is dissipated without violent explosion.

This application is a division of my copending aggplication Serial No. 158,688, filed August 12,

I claim:

1. In a locomotive firebox, a plurality of circulator devices each having at least one outlet portion connected with the crown sheet and an inlet portion extended transversely of the firebox, said circulator devices being spaced from each other longitudinally of the firebox, with the inlet portion of a forward circulator disposed at a lower elevation than the inlet portion of a circulator to the rear of the first circulator to provide a plurality of arch brick supports lying generally in a plane extended upwardly and rearwardly from a lower forward portion of the firebox, and said inlet portions being curved or arched transversely of the firebox in planes substantially at right angles to the plane aforesaid, and arch brick supported on the inlet portions of the circulators.

2. A construction in accordance with claim 1, in which the outlet portions of the circulators have their upper outlet ends extended substantially perpendicularly to the crown sheet.

3. In a locomotive firebox, a plurality of cir culator devices each having at least one outlet portion connected with the crown sheet and an inlet portion extended transversely of the firebox, said circulator devices being spaced from each other longitudinally of the firebox, with the inlet portion of a forward circulator disposed at a lower elevation than the inlet portion of a circulator to the rear of the first-circulator to provide a plurality of arch brick supports lying generally in a plane extended upwardly and rearwardly from a lower forward portion of the firebox, and said inlet portions being curved or arched transversely of the firebox in planes substantially at right angles to the plane aforesaid, and arch brick supported on the inlet portions of the circulators, the lower end of the outlet portion of each circulator extending substantially in the plane in which the inlet portion is arched, and the upper end of the outlet portion of each circulator extending substantially perpendicularly to the crown sheet.

CHESTER A. SIEGEL. 

